Data visualization applications enable a user to understand a data set visually, including distribution, trends, outliers, and other factors that are important to making business decisions. Some data sets are very large or complex. Various analytic tools can be used to help understand the data, such as regression lines, average lines, and percentile bands. However, analytic functionality may be difficult to use or hard to find within a complex user interface. In addition, analysis sometimes requires using analytic functions on two or more subsets of data at the same time